DATA BLOCK MIGRATION

• US 20180356983A1
• Filed: 06/12/2018
• Published: 12/13/2018
• Est. Priority Date: 10/04/2010
• Status: Active Grant

• Current Assignee: Quest Software, Inc.
• Original Assignee: Quest Software, Inc.
• Inventors: Jayaraman, Vinod, Dinkar, Abhijit, Taylor, Mark, Rao, Goutham, Root, Michael E., Bashyam, Murali
• Granted Patent: US 10,929,017 B2
• Time in Patent Office: Days
• CPC Class Codes: G06F 16/1748 De-duplication implemented within the file system, e.g. based on file segments de-duplication techniques in storage systems for the management of data blocks G06F3/0641
• CPC Class Codes: G06F 16/182 Distributed file systems
• CPC Class Codes: G06F 3/0604 Improving or facilitating administration, e.g. storage management
• CPC Class Codes: G06F 3/0608 Saving storage space on storage systems
• CPC Class Codes: G06F 3/0641 De-duplication techniques
• CPC Class Codes: G06F 3/0643 Management of files
• CPC Class Codes: G06F 3/0647 Migration mechanisms
• CPC Class Codes: G06F 3/0667 at data level, e.g. file, record or object virtualisation
• CPC Class Codes: G06F 3/067 Distributed or networked storage systems, e.g. storage area networks [SAN], network attached storage [NAS]

Abstract

Techniques and mechanisms are provided for migrating data blocks around a cluster during node addition and node deletion. Migration requires no downtime, as a newly added node is immediately operational while the data blocks are being moved. Blockmap files and deduplication dictionaries need not be updated.

Claims

1. A method, comprising:

receiving a request to add a new node from a data storage cluster, the data storage cluster maintaining a plurality of deduplicated data segments in a plurality of suitcases at particular nodes in the data storage cluster, wherein the plurality of suitcases include datastore suitcases created after optimizing a file, each datastore suitcase comprising a data structure including deduplicated data segments, index information, offset information, data reference count information, and last file reference information, wherein optimizing a file includes compressing the file;

generating a plurality of new keys associated with a mapping function, the mapping function using a particular key to identify a particular node containing a particular suitcase, wherein the plurality of new keys are used to identify particular suitcases stored in particular nodes, including the new node, of the data storage cluster;

copying data including suitcases and their corresponding deduplicated data segments from the plurality of existing nodes to the new node, in accordance with the mapping function and new keys, to rebalance data across the data storage cluster,

wherein performing data access after data migration includes accessing a stub file corresponding to a virtual image of the optimized file, the stub file providing a suitcase identifier that specifies a node.